Quick-opening tool retainer jaws



Jan. 8, 1957 F. J. PROCHAZKA QUICK-OPENING TOOL. RETAINER JAWS 2 Sheets-Sheet 1 Filed April 19, 1954 Jan. 8, 1957 F. J. PROCHAZKA 2,776,841

, QUICK-OPENING TOOL. RETAINER JAWS Filed April 19, 1954 2 Sheets-Sheet 2 Unite States PatentO QUICK-OPENING T001. RETAINER JAWS Frank I. Prochazka, Racine, Wis., assignor toRacine l lydraulics & Machinery, Inc., a corporation of Wisconsin Application April 19, 1954, Serial No. 423,961

6 Claims. (Cl. 27919.4)

This invention relates to an impact orpercussion tool device and more particularly to a tamper having quickopening tamper tool-retaining jaws.

In the past, a tool has been held in a tamper by means of removable screws which, when backed off, would permit withdrawal of the tool from the tamper. This operation has been time-consuming and requires theuse of parts which could readily become misplaced during a tool changing operation.

An object of this invention is to provide new and improved quick-opening tool retaining jaw mechanism for an impact tool device including a pair of jaws which may be easily moved between opened and closed positionsby a pivoting of each jaw about its pivotal mounting.

Another object of this invention is to provide quickopening tool-retaining jaws for a railway tie tamper comprising, a pair of spaced jaws pivotally mounted to the body of the tamper and positioned oppositely of each other, and spring and plunger means for holding the jaws in spaced-apart tool-release position or in closed toolretaining position.

Another object of the invention is to provide tool retaining means for a tamper comprising a jaw supporting body portion secured to the main body of the tamper, spaced plates positioned oppositely of each other and to the sides of a recess extending through the jaw supporting body portion for receiving the shank end of a tool, a pair of pins extending between the plates and to the side of the recess, a jaw pivotally mounted on each of said pins and having a pair of intersecting surfaces substantial-v ly normal to each other and forming a corner of the jaw remote from the tool-engaging surface of the jaw, said jaw being mounted on and receiving the pin in the corner thereof and chambers in the jaw-supporting body portion receiving spring-urged plungers engageable with one or the other of said intersecting surfaces on said jaws to hold the jaws in either open or closed positions.

The objects of the invention generally set forth, together with other ancillary advantages, are attained by the construction and arrangement shown by way of illustration in the accompanying drawing, in which:

Fig. 1 is a perspective view of the tamper provided with the new and improved quick-opening jaws;

Fig. 2 is a fragmentary side elevational view of the tamper showing the two positions of the jaws;

Fig. 3 is a fragmentary view in elevation of the tamper with parts broken away;

Fig.4 is a fragmentary view in elevation of the tamper with the jaws in tool-release position; and,

Fig. is a fragmentary side view of the tamper as shown in Fig. 4. 1

While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail an illustrative embodiment of the invention with the understanding that the present disclosure is to be considered as an exemplifilice cation of the principles of the invention and is not intended to limit the invention to the embodiment illustrated. The scope of the invention will be pointed out in the appended claims,

The tamper as shown in Fig. 1 comprises a power unit, indicated generally at A, a main body portion, indicated generally at B, and a jaw-supporting body portion, indicated generally at C, which is secured to the main body portion B by means such as threaded bolts 1. Handles 2 and 3 are provided for holding of the tamper by an operator. Although not limiting the scope of my invention, the portions A and B of the tamper, as shown in Fig. 1, may be similar to the tamper shown in the prior Patent No. 2,519,477, granted August 22, 1950.

As shown in Figs. 3 and 4, the main body portion B of the tamper has a recess 4 extending longitudinally thereof which receives a hammer unit including a sleeve 5 and a head 6 which engages the impact-receiving shank end 7 of a tool 8.

The head 6 has connected thereto a spring 9 which is threaded onto the upper end 10 of the head 6, and a Whip restraining member 11 extends down within the spring 9. Positioned in the recess 4 of the main body portion B and immediately beneath the head 6 is a cushion and tool guide 15 which rests on a resilient cushion 16. The cushion and tool guide 15 is provided with a longitudinal bore 17 for receiving the upper end of the tool 8.

In operation of the device, the spring 9 is reciprocated by the power unit A to compress the spring which imparts the energy of the spring to the hammer unit as more fully described in the prior patent referred to above.

Rapid expansion and contraction of the spring 9 will result in rapid blows against the impact receiving end 7 of the tool 8 by the hammer unit.

The jaw-supporting portion C of the tamper comprises a housing 20 provided with a longitudinal recess 21, which communicates with the recess 4, for receiving the shank part of the tool beneath the impact receiving end 7 thereof and has a bifurcated lower part forming spaced end plates 22 and 23 positioned to the side of the recess 21. A pair of jaw mounting pins 24 and 25 extendbetween the plates 22 and 23 and are positioned oppositely of each other and to the side of the recess 21. A pair of jaws 26 and 27 are pivotally mounted on the pins 24 and 25, respectively, and move away from each other to an open position as shown in Figs. 2, 4 and 5 and towards each other to a closed position as shown in Figs. 1, 2 and 3.

When the jaws 26 and 27 are in closed position as shown in Figs. 1, 2 and 3, the tool will be preventedfrom dropping out of the tamper by engagement between surfaces 30 and 31 on the jaws 26 and 27, respectively, with an integral flange 32 on the upper end of the tool 8. The jaws 26 and 27 are provided with tool-engaging surfaces 35 and 36 which loosely engage the shank of the tool 8.

Disposed above the jaw pivot pins 24 and 25 are a pair of cylindrical chambers 40 and 41, respectively, in which are slidably mounted cylindrical plungers 42 and 43 which are urged downwardly into engagement with the jaws 26 and 27 by coil springs 42a and 43a, respectively.. The springs 42a and 43a are suificiently strong to prevent the weight of the tool swinging the jaws 26 and 27 to tool release position but permit manual opening of the jaws when desired.

The flange-engaging surfaces 30 and 31 intersect with surfaces 45 and 46 on their respective jaws and extend substantially normal to each other to form a corner remote from the tool-engaging surfaces 35 and 36, each jaw being pivotally mounted to its pivot pin substantially in said corners. The jaws also have meeting surfaces 3 45a and 46a which are rounded off at 45!) and 46b, re-- spectively. to permit movement of one jaw independently of the other. The tool-engaging surfaces 35 and 36 are also rounded off at 35a and 36a for the same reason.

The jaw-supporting body portion C is provided with cut-away surfaces 47 and 48 which also act to permit free swinging movement of the jaws 26 and 27 between open and closed positions. The flange-engaging surfaces 30 and 31 on the jaws 26 and 27 have a smaller pivot arm than the tool-engaging surfaces 35 and 36 in order to vary the distance between the jaws in different rotative positions thereof to permit release or confinement of the tool within the tamper depending on the position of the jaws.

T o facilitate pivoting of the jaws 26 and 27, an opening is provided in each jaw in which a bar 51 may be inserted as shown in Fig. 2.

The bar 51 may be inserted in the opening 50 in one jaw while the jaws are in aclosed position as shown in full line and the jaw may then be independently rotated to an open position, as shown in. dotted line. The other jaw may then be similarly rotated. When it is desired to close the jaws, they may be independently pivoted towardveach other by use of the bar 51;

I claim:

1. In a railway tie tamper having a main body provided with a reciprocating hammer, in combination, a jaw-supporting body portion secured to the main body portion and having a recess extending therethrough for receiving the upper impact receiving end of a tool, the

lower end of said jaw-supporting body portion being bifurcated to form a pair of jaw-mounting plates positioned oppositely of each other and on opposite sides of said recess, a pair of jaw-mounting pins extending laterally between the plates and spaced. oppositely of each other on opposite sides of the recess, a tool-retaining jaw pivotally mounted on each pin for pivotal movement between open and closed positions, each jaw having a tool-engaging surface extending parallel to the axis of said recess when the jaw is closed, each jaw also having a pair of intersecting surfaces extending substantially normal to each other and forming a corner of the jaw remote from the tool-engaging surface of the jaw, each jaw being pivotally mounted on and receiving its pin in said corner, a vertically disposed chamber above each of the mounting pins having an open end adjacent the associated jaw, a plunger vertically slidable in each chamber and. engageable with one or the other of said intersecting surfaces to hold said jaw in either open or closed position depending on the surface engaged, and spring means urging said plungers into engagement with said jaws.

2. A railway ballast tamper having a jaw-supporting body portion with a recess extending therethrou gh for, receiving the upper impact receiving end of a tool, the

lower end of said jaw-supporting body portion beingv bifurcated to form a pair of jaw-mounting plates posi tioned oppositely of. each other and on opposite sides of said recess, a pair of jaw-mounting pins extending. lat erally between the plates and spaced oppositely of each other on opposite sides of the recess, tool-retaining jaws pivotally mounted on said pins for pivotal movement between open and closed positions, each jaw having a pair of intersecting surfaces extending substantially normal to each other, a cylindrical chamber above each of the mounting pins having an open end adjacent the associated jaw, a cylindrical plunger vertically slidable in. each chamber and engageable with one or the other of said intersecting surfaces to hold said jaw in either open or closed position, and means urging said'plungcrs into engagement with said jaws.

3. .A quick-opening tool-retaining mechanism for a railway tie tamper comprising a body portion having a.

recessv extending therethrough for receiving the upper impact receiving end of a tool and a pair of jaw-mounting plates positioned oppositely of each other and on opposite sides of said recess, a pair of jaw-mounting pins extending laterally between the plates and spaced oppositely of each other on opposite sides of the recess, a tool-retaining jaw pivotally mounted on each pin for pivotal movement between open and closed positions, each jaw having a tool-engaging surface extending parallel to the axis of said recess when the jaw is closed, each jaw also having a pair of intersecting surfaces extending substantially normal to each other and forming a corner of the jaw remote from the tool-engaging surface of the jaw, each jaw receiving its associated pin in said corner, and each of said jaws having associated therewith a yieldable means engageable with one or the other of said intersecting surfaces to hold the associated jaws in either Open or closed position.

4. A percussion tool device having, in combination, a main body, a jaw-supporting body portion secured to the main body portion and having a longitudinal recess for receiving the shank of an impact receiving tool, a pair of spaced jaws pivotally mounted oppositely of each other on said jaw-supporting body portion and to the side of said recess, a pair of cylindrical chambers in said jaw-supporting portion extending parallel to said recess and located above said jaws, a spring-urged cy1indrical plunger in each chamber, there being one plunger associated with each jaw, each jaw being mounted eccentrically in order to swing toward each other to closed position and away from each other to open position, said plungers engaging the jaws to hold them in one position or the other, and means for facilitating pivotal movement of the jaws.

5. An impact tool device having, in combination, a main body, a jaw-supporting body portion secured to the main body portion and having a longitudinal recess for receiving the shank of an impact receiving tool, a pair of spaced jaws pivotally mounted oppositely of each other on said jaw-supporting body portion and to the sides of said recess, a pair of chambers in said jawsupporting portion extending parallel to said recess and above said jaws, and a spring-urged plunger in each i chamber engageable with its associated jaw, there being one plunger associated with each jaw, the jaws swinging independently toward each other to closed position and away from each other to open position, said plungers engaging the jaws to hold them in either position.

6. A railway tie tamper having quick-opening means for retaining a tool within the device comprising, a jaw supporting body portion having a recess extending therethrough for receiving the end of a tool and having a pair of parallel jaw mounting plates positioned on opposite. sides of said recess a pair of jaws pivotally mounted between said plates and movable independently about spacedparallel axes toward each other to a closed tool retaining position and away from each other to an open, tool release position, a spring-urged plunger for each jaw and engageable therewith in eitherposition of the. jaw'to maintain the jaws in one or the other of said positions, and means for facilitating pivotal movement of said jaws.

References Cited in the file of this patent UNITED STATES PATENTS 1,800,377 Downing Apr. 14, 1931 1,986,297 Smith Jan. 1, 1935 1,986,298 Smith et al. ..c Jan. 1, 1935 2,432,144 Elkins Dec. 9, 1947 2,432,331 Osgood Dec. 9, 1947 FOREIGN PATENTS 364,697 Great Britain Jan. 14, 1932 

